SDE - 2

You are given an array ‘ARR’ of length ‘N’ consisting of only ‘0’s and ‘1’s. Your task is to determine the maximum length of the consecutive number of 1’s.

For Example:

ARR = [0, 1, 1, 0, 0, 1, 1, 1], here you can see the maximum length of consecutive 1’s is 3. Hence the answer is 3.

You are given two strings BEGIN and END and an array of strings DICT. Your task is to find the length of the shortest transformation sequence from BEGIN to END such that in every transformation you can change exactly one alphabet and the word formed after each transformation must exist in DICT.

Note:

1. If there is no possible path to change BEGIN to END then just return -1.
2. All the words have the same length and contain only lowercase english alphabets.
3. The beginning word i.e. BEGIN will always be different from the end word i.e. END (BEGIN != END).

Given a string S containing digits from 2 to 9 inclusive. Your task is to find all possible letter combinations that the number could represent.

A mapping from Digits to Letters (just like in Nokia 1100) is shown below. Note that 1 does not map to any letter.

Suppose someone is trying to perform a DDOS attack on your service. You need to block requests from IPs from which number of requests are breaching threshold count in last 5 mins. 

Basically design a rate limiter.

You are given a 2D board('N' rows and 'M' columns) of characters and a string 'word'.

Your task is to return true if the given word exists in the grid, else return false. The word can be constructed from letters of sequentially adjacent cells, where adjacent cells are horizontally or vertically neighboring.

Note:

The same letter cell should not be used more than once.

For Example:

For a given word “design” and the given 2D board 
[[q’, ‘v’, ‘m’, ‘h’],
 [‘d’, ‘e’, ‘s’, ‘i’],
 [‘d’, ‘g’, ‘f’, ‘g’],
 [‘e’, ‘c’, ‘p’, ‘n’]]

The word design can be formed by sequentially adjacent cells as shown by the highlighted color in the 2nd row and last column.